This invention relates to improvements in a control device for controlling an elevator system.
As one of means for controlling the movement of an elevator car, it has been common practice to control the elevator car through the medium of a model proportionally reducing the actual movement thereof. That means, however, is too insufficient in accuracy to accurately land the car on a desired one of the landing floors. In order to compensate for this insufficient accuracy, one landing switch for each landing floor could be disposed in each elevator shaft to be operated with the associated elevator car approaching each floor. Alternatively, it could be attempted to improve the landing accuracy by additionally using a second model smaller in reduced scale than the above-mentioned model to be effective for each of zones of landing operations alone.
The use of the landing switches has required various implements disposed on each elevator car and within each elevator shaft. This has encountered problems in view of the space occupied by such implements and the expensiveness, while it has been attended with dangers that may occur in adjusting, checking and maintaining those implements. The second model, though it is small in reduced scale, has included a fair error because its length is considerably reduced as compared with the actual distance put under control thereof within the associated shaft. Thus the use of the second model has not resulted in the elimination of the insufficiency of the desired accuracy.